The blood acetate clearance curve had a biphasic character during the ethanol withdrawal period in ethanol-dependent rats. Blood acetate concentrations remained relatively stable for 15 to 20 hours, during which time blood ethanol was removed in a rectilinear fashion. Blood acetate concentrations remained on a plateau at approximately 8 to 9 mg/dL. When blood ethanol concentration decreased to approximately 80 to 50 mg/dL, blood acetate began to decrease very rapidly. The leveling off of the blood acetate concentrations at a plateau suggests that blood acetate concentrations are probably related to the rate of ethanol oxidation. The blood acetate curve of naive rats after a single dose of ethanol had a shape similar to the acetate curve in rats rendered physically dependent on ethanol. Concentrations of acetate similar to those in ethanol-dependent rats have been previously found in human alcoholics participating in a free drinking paradigm.